1. Field of the Invention
Embodiments of the present invention relate to containment enclosures. More particularly, embodiments of the present invention relate to double-walled containment enclosures.
2. Background Information
Containment enclosures, sometimes called turbine enclosures or sumps, are currently used to provide a housing for various components, including, for example, a submersible pump, a termination point for double-wall piping, and/or access to fittings or accessories on the top of an underground tank. Containment enclosures may be constructed of fiberglass reinforced plastic (FRP), which is a proven material for long-term performance, or other materials such as polyethylene, polypropylene, other plastics, or combinations of these materials.
A typical containment enclosure is often supplied with non-sealed, watertight, or sealed FRP lids to block access to the interior of the containment enclosure. In a typical installation, a containment collar is affixed to the storage tank and has an adhesive channel opposite the portion mounted to the tank to allow for a sealed joint with the containment enclosure body. The containment enclosure body is typically a cylindrical or polygon shaped body that also includes an adhesive channel to allow for a sealed joint with a reducer or flat top. The reducer or flat top allows for the addition of a lid of the same diameter as the enclosure or for narrowing of the enclosure opening with a lid of a diameter less or equal to that of the enclosure body. As an alternative, the adhesive joints may be replaced with field applied FRP lay ups attaching the parts together.
Because of the materials contained in these storage tanks, for example gasoline or other hazardous liquids, more and more stringent regulations have led to the use of double-walled storage tanks to allow for extra protection from leaks as well as the ability to detect leaks. Although much of the focus has been on maintaining the integrity of the tank itself, as the need for safer and more reliable systems increases, it may become more desirable to have an entire system, tank and containment enclosure combined, with the safety and durability now embodied in the tank itself.
Similarly, underground containers are also used for holding and detecting fuel leaks under fuel dispensing pumps, for piping transitions, or for vapor recovery systems. These containers can also benefit by the use of containment enclosures for the same reasons as previously noted for tanks.